Swimming pool cleaners in various guises exist, each one sporting features claiming to be superior to the other. The purpose of this invention is to produce a cleaner that is not only more compact than the existing cleaners of this configuration but also quieter and more durable.
Typically, cleaners of this configuration use some or other valve to interrupt or partially interrupt the flow of water through the said valve. This interruption in the flow of water will cause the cleaner to jump forward in a stepwise manner following each cycle of valve interruption.
Some cleaners on the market rely on a flexible valve membrane ref U.S. Pat. No. 4,642,833 Stoltz; Andries J. (Pretoria, ZA), Kallenbach; Dieter H. F. (Sandton, ZA) to interrupt flow while others rely on a rigid valve member ref U.S. Pat. No. 4,133,068 Hofmann.
Both of these valves have advantages and disadvantages. Typically the flexible valves will be better in Sandy environments and quieter in operation, whereas the harder valves will be more durable though noisier.
What all these and current valve interruption flexible disk type cleaners have in common is fitment of a rigid tube in between the valve and cleaner hose. This tube is necessary to ‘tune’ the interruption cycle so the valve does not cycle too slow or fast. Typically the longer the rigid tube the slower the valve will cycle. In other cleaners, specifically the partial water interruption cleaners, twin tubes are of sufficient length to create necessary shockwave effect in each tube to move the cleaner forward (ref U.S. Pat. No. 4,023,227 Chauvier). The necessity of this tuning tube makes the current group of pool cleaners seem noisy and bulky in appearance.
Another negative aspect of rigid ‘tuning’ tubes is that by creating a shockwave within the tubes the water-hammer effect creates a momentarily reverse flow situation thereby slowing down flow and debris pick-up.
The scope of this invention is to combine the best properties of each type i.e. reliability of the hard valve and low noise levels of the diaphragm type valves in a much smaller package.
While a similarity may exist between the Hofmann patent and this invention in that both uses an oscillating valve with a means of interruption of flow through a secondary channel the similarity ends there in that Hofmann describes a baffle plate functioning only as a means to restrict flow to the secondary passage.
Furthermore the partition member in the Hofmann patent has a serious drawback in that the cleaner would block very easily with debris, even a small grain of sand has proved to stop the cleaner when it entered the secondary channel, this is because Quote ‘The shape of the valve protruding the peak enables the space between the valve and partition member 22 to remain substantially constant as the valve moves between its terminal positions and is also symmetrical’
Because the shape is constant and the partition member and valve surfaces are very close together throughout the valve oscillation process the smallest piece of debris entering between the two surfaces would become wedged and stop the unit.
For this invention an insert also referred to as a flow-control-diverter is provided to perform a multi task operation in that it functions as a means:    1. Control flow between a primary and secondary channel to effectively negate the use of a rigid or tuning tube between valve and hose.    1. In conjunction with a secondary feature create hydraulic valve cut off for extremely quiet operation and durability    1. Guide debris by means of guide-ribs to primary flow channel    1. Create a plenum chamber of sufficient volume between insert and valve to allow flow and debris entering the secondary channel to proceed uninterrupted to the outlet    1. Interrupt flow
This invention is unique in that the tuning of the valve cycle frequency does not depend on the length of a rigid or tuning tube at the outlet side of the valve in-between the valve and hose but rather on a flow pattern created by diverting and regulating flow to the primary and secondary channels on the inlet side of the valve.
The design differs from other designs of this type that focus on restricting flow to the secondary channel to a maximum in that it actually specifies a fair amount of flow volume be diverted to the secondary channel.
As a consequence of this a larger volume of water will flow through the cleaner under all operating conditions in comparison with the more restrictive means of other designs
Correctly balanced the cleaner will although it uses a hard material valve to interrupt the flow of water be quieter even than a flexible membrane valve.
This low noise levels are achieved by creating a ‘water cushion’ effect so the valve will in closing return to open before it actually makes contact with a hard surface in the body housing.
In the open position valve may make brief contact with the housing but the force is so low that it can barely be heard under normal operating conditions.
In the preferred embodiment debris is diverted into a main (primary) flow channel whereas a secondary channel will allow mostly water flow and smaller debris through.
To prevent large debris from entering the secondary channel an insert with integral guides is provided to divert debris to the main channel, although smaller debris may from time to time pass through the secondary channel.
Furthermore the insert is devised to sufficiently interrupt flow to the main channel when valve closes against it to create a shockwave to propel cleaner in a stepwise manner.
The insert is shaped as to create an enlarged gap between the valve inlet face and insert as valve returns to open position so as to allow debris entering the secondary channel to progress freely to outlet.
In conjunction with the insert hydraulic cut-off technology creates extremely quiet operation
Valve has cutaway sides and hinged mechanism for improved durability and debris digestion.
The invention also comprises of other unique features such as anti-blocking swivel, split outer housing integrated with inner housing kept etc.